Method and machine for assembling washers with rotary fasteners



p 6 1955 M. H NIELSEN METHOD AND MACHINE FOR ASSEMBLING WASHERS WITH ROTARY FASTENERS 5 Sheets-Sheet 1 Filed Aug. 3. 1950 INVENTOR.

Sept. 6 1955 M. H. NIELSEN METHOD AND MACHINE FOR ASSEMBLING WASHERS WITH ROTARY FASTENERS 5 Sheets-Sheet 2 Filed Aug. 3. 1950 Sept 6 1955 M. H. NIELSEN METHOD AND MACHINE FOR ASSEMBLING WASHERS WITH ROTARY FASTENERS 5 Sheets-Sheet 5 Filed Aug. 5, 1950 Ill lllllll BY Wm Se t. 6 1955 M. H. NIELSEN METHOD AND MACHINE FOR ASSEMBLING WASHERS WITH ROTARY FASTENERS 5 Sheets-Sheet 4 Filed Aug. 3, 1950 zNVENTOR.

M M M 1 W p 6 1955 M. H. NIEL N 2,716,761

METHOD AND MACHINE F ASSEMBLING WASHERS WITH ROTARY FASTENERS Filed Aug. 3, 1950 5 Sheets-Sheet 5 a -WW army/2%;

United States Patent METHOD AND MACHHWE FOR ASSEMBLING WASHERS WITH ROTARY FASTENERS Moritz H. Nielsen, Chicago, Ill., assignor to Illinois Tool Works, Chicago, 111., a corporation of Illinois This invention is concerned with the assembly of washers and fastening elements telescoping therewith particularly toothed lock washers and rotary threaded or 'threadable fastening elements such as screw blanks.

A broad object of this invention is the provision of apparatus for assembling rotary fastening elements and washers at a higher rate of speed than heretofore thought possible.

A more particular object of this invention resides in the provision in apparatus for assembling a succession of rotary fasteners and a strip of interconnected washers, of means for severing the washers from the strip at a maximum rate of speed.

A further object of this invention is the provision of apparatus for assembling a succession of fastening elements and a strip of interconnected washers wherein each assembled washer and fastening element is severed from the remainder of the strip by twisting the washer out of the plane of the strip.

A more specific object of this invention is the provision of apparatus as .set forth in the preceding object in which each succeeding washer is twisted about the longitudinal axis of the washer strip to sever it from the strip.

Another object of this invention is the provision of apparatus for assembling a strip of lock Washers having twisted teeth with confronting teeth of adjacent washers interconnected and a succession of rotary fasteners, and thereafter twisting the washers in the direction in which the teeth are twisted to separate the washers readily without distorting the washers.

A further object of this invention is the provision of apparatus for telescopically assembling a succession of fastening elements and a strip of interconnected washers wherein the washer strip is moved continuously and succeeding washers of the strip and fastening elements assembled therewith are severed from the strip by revolving the fastening elements to twist the washers about the longitudinal axis of the washer strip while continuing to move the washer strip longitudinally.

Another object of this invention is the provision in apparatus for assembling a strip of interconnected washers and a succession of rotary fastening elements, of more efficient means for feeding the strip than any heretofore known.

Yet another object of this invention is the provision in apparatus for assembling a curved strip of interconnected washers and a succession of rotary fastening elements, of improved means for feeding the curved strip at a high rate of speed without danger of breaking the strip.

An object of this invention is the provision in'apparatus for telescopically assembling a succession of fastening elements and a strip of interconnected washers, of means for feeding the washer strip independently of the means for advancing the fastening elements.

This invention contemplates the provision of apparatus for telescopically assembling fastening elements and washers in a continuous strip by gradually converging ice the fastening elements with a strip of Washers, the washer strip preferably being supplied in the form of a helical coil. For utmost production speed, the washer strip is moved continuously and is fed by means other than the fastening element feeding mechanism. A section of metal is displaced on each assembled fastening element and washer to retain them is assembled relation after which each assembled fastening element and washer is severed positively from the remainder of the strip with greater speed and certainty than heretofore thought possible by twisting it out of the plane of the strip while the strip is moving longitudinally. Each separated washer and fastening element assembled therewith then may be stored or transferred directly to one or more thread rolling machines.

Other and further objects and advantages of the present invention will be apparent from the following description of an illustrative embodiment of my invention when taken in conjunction with the accompanying drawings in which:

Fig. 1 is a perspective view of an assembly machine embodying the principles of my invention;

Fig. 1a is an enlarged fragmentary sectional view along the line 1a1a of Fig. 1;

Fig. 2 is a top view of the machine, certain parts being broken away for clarity of illustration;

Fig. 3 is a fragmentary side view of the machine;

Fig. 4 is an enlarged sectional view taken along the line 4-4 of Fig. 3;

Fig. 5 is a top view of the part of the apparatus for forming temporary retainers on the shanks of screw blanks to retain assembled screw blanks and washers in assembled relation;

Fig. 6 is a sectional view taken along the line 6-6 of Fig. 5;

Fig. 7 is a fragmentary elevational view showing the washer strip driving mechanism;

Fig. 8 is an enlarged sectional view of a portion of the washer strip driving mechanism;

Fig. 9 is a fragmentary side view of the retainer forming mechanism and washer strip driving mechanism;

Fig. 10 is a perspective view of part of the twisting head for severing assembled screw blanks and Washers from the remainder of the washer strip;

Fig. 11 is a sectional view of the twisting head taken substantially along the line 11-11 of Fig. 3;

Fig. 12 is a sectional view taken along the line 1212 of Fig. 11;

Figs. 1322 are a series of diagrammatic views showing the succession of operations as a washer is twisted from the strip, each even numbered figure being taken substantially along the section line of the preceding odd numbered figure as indicated;

Fig. 23 is a plan view of a section of the washer strip operated upon; and

Fig. 24 is an enlarged view of the assembly track taken along the line 2424 of Fig. 1.

Referring first to Figs. 1, 2 and 3 for a general description of my apparatus, there will be seen a supporting stand 26 having inclined longitudinal frame members 28 and 30. A lower supporting table 32 is carried by the frame members 28 while first and second upper inclined tables 34 and 36 respectively are supported by the inclined frame member 30. The upper inclined table 34 supports an upstanding column 38 which in turn supports a blank feed chute 40 feeding headed screw blanks 41 by gravity from a screw hopper 43.

A washer feed drum 42 is rotatably and pivotally mounted atop the lower inclined table 32 and carries a helically coiled nested stack 44 of a strip 46 of lock washers. The lock washers 43 (Fig. 23) preferably are of the type having radially extending twisted teeth 45 with adjacent teeth of successive washers interconnected as at 47. The entire strip preferably is hardened after being coiled helically and cannot be straightened without danger of fracture of the interconnections 47.

The assembly mechanism 49 includes a screw blank driving or feeding disc 48 mounted above the drum 42 and concentrically therewith and an assembly track 50 underlying the periphery of the disc 48. The assembly track is provided with a washer guideway receiving the washer strip 46 and progressively approaching the plane of the drive disc 48 and further is provided with a screw blank shank receiving slot disposed transversely of said guideway and aligned throughout most of its length with the periphery of the disc 48. The periphery of the disc is provided with alternate recesses 52 and teeth inclined in the direction of rotation of the disc. Screw blanks 41 are fed from the screw feed chute 40 into the assembly track where the shanks of the blanks are engaged beneath the heads by the periphery of the drive disc 48 to advance the screw blanks rapidly and positively with the assistance of gravity.

After the screw blanks 41 have been assembled with the washers of the strip 46 in the assembly track 50, the screw blanks and washer strip pass along a curved guide track 54 to retainer forming mechanism 56 whereat the shanks of the screw blanks are swaged below the washer strip to displace sections of metal from the shanks to retain the blanks and washers in assembled relation. The washer strip and assembled blanks then pass along an extension track 58 to a washer strip feeding mechanism 60 from whence they pass to a continuously rotating twisting head 62 which severs successive washers from the remainder of the strip. From this point the individual assembled washers and screw blanks may pass to a storage container or directly to one or more thread rolling machines wherein threads are rolled on to the shanks of the screw blanks. The thread rolling operation removes any vestige of the temporary retainers on the screw blank shanks and increases the outside diameter of the shanks sufficiently to retain the screws and washers in assembled relation.

Screw blank feeding mechanism The screw blank feed chute 40 comprises a pair of rails 64 spaced apart just slightly greater than the diameter of the shanks of the screw blanks 41 and supported by a pair of upstanding flanges 66 forming a part of a bifurcated bracket 68 integral with the top of the column 38. A base 70 integral with the column 38 and perpendicular thereto is secured to the table 34 by any suitable means such as a plurality of bolts. The rails 64 are maintained in substantial parallelism with the table 34 which allows the screw blanks 41 to be fed from the hopper 42 of any suitable type by gravity with their heads resting atop the rails 64 and their shanks depending between the rails. A third rail 72 is spaced above the rails 64 by bracket 74 a distance just slightly greater. than the height of the screw blank heads and is located centrally of the rails 64 to prevent the screw blanks from popping up out of their position between the rails.

The screw blank feed chute 40 is curved near its lower end to merge with the assembled mechanism 49. In order that the screw blanks 41 may be delivered to the assembly mechanism smoothly, a thin metal arm 74 is mounted on a'block 76 carried by the innermost of the rails 64; The arm 74 underlies the heads of the screw blanks and supports the blanks until their shanks are properly located in the recesses 52 of the drive disc 4-8 and in the assembly track 50, at which time they are allowed to drop slightly to rest with their heads atop the drive disc and assembly track.

An arcuate finger 78 (Figs. 2 and 24) is secured to the outermost of the rails 64 at a recessed location therein by means such as screws and extendsarcuately with its-inner surface holding the screw blank shanks in engagement with the drive disc 48. The upper edge of the finger 73 lies in the plane of the upper surface of the drive disc 48 so that the screw blanks are supported beneath their heads evenly from opposite sides. The finger 7S tapers to a point 79 whereat it is succeeded by the upper surface of the outermost rail of the guide track 50.

A screw blank sensing mechanism 80 is provided in cooperation with the screw blank feed chute 40 to prevent operation of the assembly machine if no screw blanks are being fed down the feed chute. The screw blank sensing mechanism comprises a bracket 82 overlying the upper or third rail 72 and supported by fingers 84 on each side of the rail 72, the fingers resting on the heads of the succession of screw blanks 41. The lower end of the bracket 82 is pivoted at 85 to an arm which. rests atop the operating plunger of a normally closed switch 86 mounted on the column 38. in the event that no screw blanks are fed through the chute 40, the weight of the bracket 82 and arm to which it is pivoted causes it to drop slightly to depress the switch actuating the plunger and pivot the switch 86. The switch 86 is connected either in series with an electric motor driving the assembly machine or in circuit with a relay controlling the actuation of the driving motor, so that opening of the switch 86 stops the machine. 1

The washer strip supply mechanism The drum 42 is frictionally mounted on a shaft 87 (Fig. l) journalled in suitable antifriction bearings carried by an arm 88 pivotally mounted on the lower inclined table 32. The arm 83 is secured to the table by a bolt 90 passing through a longitudinally elongated slot 92 near the end of the arm opposite the drum. A bolt $3 fitting in an arcuate slot in the side of the arm clamps the arm in position. By means of the bolt and slot connection, the drum may be swung to one side of the machine to receive a. helically coiled nested stack 44 of a Washer strip 46. The stack 44 rests on a peripheral flange 94 at the bottom. of the drum and an upstanding flange 95 (Fig. la) on the periphery of the bottom of the drum extends upwardly therefrom properly to locate the nested washers of the strip. After the stack of washers has been installed on the drum, the drum is restored to the position shown in the drawings and the bolts 90 and 3 are tightened to se' cure the arm 88 against movement.

An upstanding arm 96 is secured to the inclined longitudinal frame member 30 by means of a belt 98 passing through a lateral flange 1&0 on the arm. A roller 102 is carried by the arm to support the washer strip 46 and lead it smoothly to the assembly mechanism 49.

To prevent operation of the machine when no washers are being supplied, there is provided a washer strip sensing mechanism 104. The Washer strip sensing mecha nism includes a roller 106 carried at the end of an angular arm 108 pivotally carried by the column 38. A normally closed switch 110 similar to the switch 86 and controlling the operation of the drive motor in the same manner is carried by the column 38 and has a switch stunting plunger underlying the arm 108. If for any reason the washer strip is not fed over the roller 1612 to the assembly mechanism 49, the roller 106 and the arm 108 drop, thus depressing the actuating plunger of the switch 110 and stopping the driving motor.

The assembly mechanism A V-shaped arm 112 is supported at one end thereof by a supporting block 114 carried by a support upstanding from the second upper table 36. A shaft 116 is journalled for rotation in the arm 112 at the apex thereof. The drive disc 48 is secured to the shaft 116 for rotation therewith by means of a hub 118 fastened to the disc by screws 117 and secured to the shaft by a key 119 and a set screw 121.

The assembly track 50 as noted heretofore underlies the periphery of the drive disc 48. The assembly track comprises a pair of spaced rails 120 interconnected by a lower wall 122 and an upper wall 124 from the strip receiving end of the track to a point adjacent the convergence of the screw feed chute 40 with the track, at which point the upper wall is discontinued and the lower wall is slotted to accommodate the shanks of the screw blanks 41. The inner faces of both rails 120 are longitudinally slotted adjacent the lower wall 122 and define therewith a washer strip guideway.

The assembly track 50 is adjustably carried by a bracket 126 (Fig. 1) upstanding from the first upper inclined table 34. The inner of the two rails 120 is of uniform height and underlies the drive disc 48 except at the discharge end of the assembly track at which point the inner rail is cut down and thereafter the entire track recedes from the periphery of the drive disc. The outer track 50 is of varying height, being cut down to allow screw blanks 41 from the screw feed chute 40 to enter and rising thereafter to form with the arcuate finger 78 a supporting surface lying in the same plane as the top surface of the drive disc 48 whereby screw blanks are supported beneath opposite sides of the heads with no tendency to tip. The outer rail 120 is cut down at the discharge end of the assembly track.

The washer strip guideway of the assembly track 50 converges with the plane of the drive disc 48 and the upper surface of the outer rail of the assembly track so that washers carried thereby and screw blanks carried by the drive disc and assembly track are gradually brought into telescoping relation substantially linearly relative to one another as may be seen in Fig. 24. At the discharge end of the assembly track where the rails 120 are cut down, washer strip guideway joins the top surfaces of the rails slightly to one side of the drive disc 48 at which point the screw blanks are forced into completely telescoped relation with the washers of the strip by the end of a leaf spring 128 carried by a bracket 130 upstanding from the assembly track 50.

The retainer forming mechanism The guide track 54 comprises a continuously curved rail having a deep central slot accommodating the shanks of the screw blanks 41 which it receives from the assembly track 50, the washer strip and screw blank heads riding atop the upper surface of the rail. The track is supported by a bracket 132 upstanding from the second upper table 36. Screw blanks and the washer strip carried by the guide track 54 are delivered to the retainer forming mechanism 56 which comprises a pair of swaging wheels 134 and 136 (Figs. 2, 5, 6 and 9) accommodated by recesses 164 in the track 54. The wheels are fixed respectively to shafts 138 and 140 which are journalled in suitable bearing sleeves in a bracket 141 upstanding from the second upper inclined table 36 and a bracket extending from the supporting block 114. The shafts are geared together by spur gears 142 and 144 at their lower ends so that the swaging wheels 134 and 136 rotate in unison.

The swaging wheels 134 and 136 are provided with spaced substantially semicylindrical slots 146 about their peripheries, the slots being spaced an appropriate distance to receive the shanks of successive screw blanks 'as the wheels rotate and the blanks advance. Swagers 148 and 150 are secured to the tops of the swaging wheels 134 and 136 respectively by any suitable means such as screws 152. The swagers are provided with spaced teeth 154 and 156 extending over each slot 146. The teeth are tapered to a point and have inclined upper surfaces so that they bite into the shanks of the screw blanks and force narrow sections 158 of metal outwardly and upwardly to form temporary retainers below the washer strip.

A bridge 160 (Figs. 1 and 2) spans the swaging wheels and is secured as by screws to legs upstanding respectively from the bracket 141 securing the swaging wheel shaft 138 and the supporting block 114. A curled over leaf 6 spring 162 is carried by the bridge I60 and has its free end contacting the heads of the screw blanks to hold them in fully telescoped relation with the washer strip while the temporary retainers are being formed on the shanks of the screw blanks. The track 54, which is cut away at 164 to accommodate the swaging wheels 134 and 136, continues a short distance past the swaging wheels to a washer strip driving wheel 166 (Figs. 2, and 7-9). The driving wheel 166 has integral hubs 168 and 178 keyed or pinned to a shaft 172 angularly disposed relative to the second upper table 36 and rotatably journalled in a support 174 upstanding from this table.

The wheel 166 has a periphery 176 forming a section of a cone and the surface of the wheel adjacent the hub 168 likewise comprises a conical surface. The wheel is provided with a peripheral slot 178 parallel to the conical surface adjacent the hub 168 in order to receive the shanks of the screw blanks 41. The peripheral surface 176 is provided with a plurality of substantially semicircular recesses 180 on either side of the slot 178 to receive the washers of the washer strip 46 and also the heads of the screw blanks 41 assembled therewith. As the wheel 166 rotates it drives the washer strip and due to its conical periphery 176, moves the strip along a curved path as best may be seen in Fig. 2.

A wall 182 extends upwardly from the second upper table 36 and is substantially perpendicular thereto. A supporting arm 184 is secured to the top of this wall by means such as a bolt and extends outwardly above the washer strip driving wheel 166. A longitudinally curved shoe 186 depends from the free end of the arm 184 and contacts the heads of the screw blanks 41 lightly to hold them in fully seated position in the wheel 166 and adjacent tracks. The shoe 186 is secured to the arm 184 by means of a bolt 188 passing through the arm and threaded into a hub 190 integral with the shoe.

The washer detaching mechanism A wall 192 extends upwardly from the table 36 to which it is secured by an angle bracket 194 screwed to the wall and table. The wall 192 is also perpendicular to the wall 182 to which it is secured. The wall 192 is provided with a circular aperture 195 (Fig. 11) within which is mounted a circular plate 196. The circular plate 196 is provided with a portion 198 journalled in the aperture 195 and with a portion 200 of enlarged diameter fitting in part substantially against the wall 192. An axial aperture 202 extends through the circular plate 196 and is of larger diameter at the free or outer end than at the other.

A twisting plate 284 (see also Figs. 9, 10 and 12) having an outside diameter slightly greater than the diameter of the aperture 195 is secured to the circular plate 196 by means such as spaced screws 28-6 and thus secures both the circular and twisting plates in position. The twisting plate 204 is provided with a raised central hub 268. Three radial slots 210 spaced at 120 extend completely through the twisting plate 284 and communicate with the aperture 202 in the circular plate 196. These slots have a width just slightly greater than the diameter of the blanks of the screw shanks and terminate in a central bore 212 of just slightly greater diameter than that of the washers of the strip 46 and the heads of the screw blanks 41. As best may be seen in Figs. 10 and 12 the outer face of the hub 208 has a recessed sector 214 lying to one side of each of the slots 210 in the direction of rotation of the plate. Each sector 214 has it gradually curved leading surface 216 to provide a smooth progressive entrance into each sector 214 and slot 210.

A guide carrying block 218 having a recess 228 is supported by the wall 182 and extends nearly to the path of the screw blanks. A second guide carrying block 222 is supported by the wall 192 and has a recessed angularly disposed arm 224 extending into confronting relation with the guide carrying block 218. Inserts or guides 226 and 228 in the recess 220 of the guide block 218 and on the recessed arm 224 respectively have curved confronting edges forming a guideway 230 which is a continuation of the curve formed by the track 58 and drive wheel 166. The upper surfaces of the confronting edges of the guides are bevelled at 232 and 234 respectively to lead the washer strip and assembled screw blanks smoothly from the periphery of the drive wheel 166 to the twisting plate 204. The inserts are relieved at 236 and 238 adjacent their confronting edges and below the bevelled portions 232 and 234 in order that they may be placed as closely as possible to the washer strip driving wheel 166. The confronting surface 240 of the recessed arm 224 and the short continuation thereof in the insert 228 are relieved at the leading edge to provide clearance for the wheel 166.

The driving mechanism The entire assembly machine is driven by a single electric motor (not shown) operating a pulley 242 (Fig. 2) through the intermediary of a flexible belt- 244. The pulley is fixed to a shaft 246 journalled in a support 248 upstandingfrom the second upper inclined table 36 and in a sleeve bearing 250 carried beneath the supporting block 114. A worm 252 on the shaft 246 drives a worm wheel on the shaft 140 of the swaging wheel 136 and this shaft in turn drives the shaft 138 of the swaging wheel 134 through the intermediary of the spur gears 142 and 144.

A spur gear 254 is secured to the end of the drive shaft 246 by means of a pin or the like in a hub 256 formed integral with the gear. The spur gear 254 is meshed with a gear 258 carried on the end of a shaft 260 (see also Figs. 3 and 4) by means of a pin or set screw in a hub 262 integral with the gear, the gear 258 fitting in a recess in the wall 122. The shaft 260 is carried by a column 264 upstanding from the second upper table 36 and carries a larger spur gear 266 spaced from the gear 258 by the hub 262 and secured to the shaft 264) by a pin or set screw carried by a hub 268. The periphery of the circular plate 196 is provided with gear teeth 270 so that the plate 196 forms a gear meshed with the gear 266. An idler gear 272 is rotatably mounted by means of a collar 274 on a shaft 276 carried by the upstanding wall 192 and is meshed with the gear teeth 270 of the circular plate 196. The idler gear 272 is also meshed with the spur gear 278 secured to a shaft 280 by means of an integral hub 282 and a pin or the like. The shaft 280 is carried by a bracket 2S4 extending from the upstanding wall 182. A bevel gear 286 is secured to the opposite end of the shaft 280 by means of a pin or a set screw carried by a hub or collar 288.

An idler bevel gear 290 is meshed with the bevel gear 286 and carried by a shaft 292 extending from the wall 182. The idler bevel gear 290 is spaced from the wall by means of a collar posed relative to the wall 132 and extends through an aperture therein and is journalled in supports 298 and 300 carried by this wall. A bevel gear 302 is secured to one end of the shaft 296 by means of a set screw or pin in a hub 304 on the gear and is meshed with the idler bevel gear 290 to drive the shaft 296. A worm 306 is secured to the shaft 296 by means of a pin or set screw in a hub 308 integral with the worm. The worm engages a worm wheel 310 secured to the shaft 172 of the washer strip driving wheel 166 (Fig. 7) by means of a hub 312 carrying a pin or set screw.

The shaft 260 carried by the column 264 upstanding from the table 36 has keyed to its outer end a worm 314 (Figs. 2 and 4) slidably located on the shaft by means of a depending arm 316 of an angle bracket 318 and a collar 320. The angle bracket is adjustably carried atop the column 264 by means of bolts 322 extending through longitudinal slots 324 in the bracket and threaded into the top of the column. A set screw 326 in the depending arm 316abuts the column 264 for'fine adjustment-of the 234. A shaft 296 is obliquely dis- 8 position of the bracket 318. A set screw 328 carried by the arm'316 extends into a peripheral slot in the hub 329 to fix the worm 314 against axial movement relative to the bracket 318. A set screw 330 in the collar 320 allows the collar to be locked in place on the shaft 260.

A shaft 332 (Figs. 1-3) upstanding from the second upper table 36 is supported by the free end 334 of the V-shaped arm 112 and by a pedestal 334 upstanding from the table 36. A collar 336 below the table 36 prevents upward movement of the shaft 332 while a head 338 on the shaft prevents downward movement thereof. A worm wheel 340 is carried by the shaft 332 in engagement with the worm 314 and a spur gear 342 is also carried by the shaft 332 and rotates with the worm wheel 340. The spur gear 342 is meshed with an idler gear 344 on a headed shaft 346 depending from an intermediate position of the V-shaped arm 112 in which it is secured as by means of a pin 348. A spur gear 350 meshed with the idler gear 344 is fixed to the shaft 116 of the drive disc 48 below the V-shaped arm 112. A slidable collar 352 is secured by a set screw to the lower end of the shaft 116 and the upper end of the drum shaft 87 and cooperates with shoulder portions 353 on the shaft 116 and the drum shaft 87 to form a releasable drive connection between these two shafts.

Operation of the assembly machine The bolts 90 and 93 (Fig. l) securing the arm 88 on 30 which the drum shaft is mounted are loosened and the detachable shaft coupling is disconnected by raising the collar 352 following which the drum 42 is shifted from beneath the assembly mechanism 49. A helically coiled stack 44 of a continuous washer strip 46 is placed over the drum, resting on the flange 94 at the bottom thereof with the upstanding flange 95 maintaining the bottom of the stack in proper position. The drum is then restored to the position shown in the drawings.

The washer strip 46 is then positioned over the roller 1 102, under the roller 106 of the washer strip sensing mechanism and inserted in the washer strip guideway of the assembly track 50. Screw blanks are fed down the feed chute and into the assembly track 50 to telescope with the washers of the strip and the assembly machine is driven by hand as the strip and assembled screw blanks are laid out by hand over the tracks 54 and 58 until the strip is engaged by the drive wheel 166. The electric drive motor (not shown) is started and acts to drive the disc 48, the drum 42, the swaging wheels 134 and 136 .of the retainer forming mechanism 56, the washer strip drive wheel 166 and the circular plate and twisting plate of the twisting head 62. The screw blanks 41 are properly spaced by the disc 48 and are driven thereby while engaging the washer strip 46 to aid the drive wheel 166 in advancing it through the assembly track, the screw blanks and washer strip movinggover converging paths to be telescoped gradually and being forced into completely telescoped relationby the leaf spring 128 at the end of the assembly track, the telescoping best being seen in Fig. 24. The assembled screw blanks and washer strip then advance along the curved guide track 54 to the retainer forming mechanism 56 where the teeth 154 and 156 of the. swaging-wheels 134 and 136 swage or displace narrow sections of'm'etal outwardly from the shanks to form temporary retainers. In addition to forming the retainers, the swaging wheels assist in driving the screw blanks 41 through the guide track. 54 and the extension track 58 forming a part thereof to the washer strip drive wheel 166. The'recesses about the periphery of the drive wheel 166 engaging the individual washers of the strip constitute the primary feeding means for the strip and advance the strip independently of the various screw blank driving means,'the shanks of the screw blanks fitting within the conical slot 178 of the drive wheel 166. From'this point the washer strip-and assembled screws pass through the guideway 230 of the twisting head 62, the bevelled surfaces 232 and 234 providing a smooth entrance so that there is no tendency for the teeth of the washers to catch. The washer strip and screws then pass into the twisting plate 204 where each washer and assembled screw is broken away from the adjacent washer as shown diagrammatically in Figs. 13-22.

As the washer strip 46 and screw blanks 41 assembled therewith approach the rearwardly extending portion 204 of the twisting plate 208, the leading assembled screw blank and washer unit, which for purposes of explanation will be referred to as assembly A, arrives with the foremost edge of the shank of the screw blank against the plane of the rear surface of the twisting plate, the twisting plate 204 having been rotated to a position such that the shank of the blank is aligned with the leading edge 216 of one of the sectors 214 as seen in Figs. 13 and 14. It is apparent that the screw head and washer of assembly A pass beyond the plane of the rear surface of the twisting plate 204 prior to this alignment, but as the upper surfaces of the guide block inserts 226 and 228 lie along a diameter of the central bore 212 of the twisting plate, the head and washer fit readily within this bore. As forward motion of the washer strip 46 and assembled screw blanks 41 continues, assembly A extends further into the sector 214 of the constantly rotating twisting plate 204 as shown in Figs. 15 and 16 until, as shown in Figs. 17 and 18, the shank of the screw blank of assembly A is aligned with the slot 210 through the twisting plate 204 at which time the shank lies entirely within the twisting plate 204. The wall of slot 210 engages the shank of the blank of assembly A and the rotating twisting plate 204 twists assembly A as it continues to advance into the twisting plate 204 through the slot 210 and central bore 212. The second assembled screw and washer, hereinafter termed assembly B, is prevented from twisting by the guideway 230 which as may be seen in Fig. 11 is of substantial depth adjacent the plate 204, so that there is a relative twisting motion between assemblies A and B. The washer teeth are twisted as the washers are formed with the result that the interconnections between the washers are thin and stretched. The relative twisting motion between assemblies A and B is in the direction that the teeth are twisted and readily snaps the interconnection 47 between the adjacent washer teeth of assemblies A and B without distorting the washer teeth. Assembly A is now free of the remainder of the washer strip. After the twisting plate 204 has rotated 120 from the position of Figs. 13 and 14 to the position of Figs. 21 and 22, assembly B has reached the position of assembly A in Figs. 13 and 14 and begins to enter the next successive sector 214 of the twisting plate 204 to be twisted from the next successive washer of the washer strip 46 in the same manner. The advancernent of assembly B into the sector 214 and slot 210 pushes assembly A ahead of it and out of the twisting plate through the aperture 202 of the circular plate 196 from whence it falls by gravity into a storage container or is fed directly to any of a plurality of thread rolling mechanisms. Continued advancement of the washer strip and assembled screw blanks and rotation of the twisting head results in rapid separation of successive assemblies in the manner set forth heretofore.

As the washer strip and screw blanks are driven by the drive disc 48 as well as by the retainer forming mechanism 56 and drive wheel 166, it is important that the disc 48 be driven in synchronism and proper phase with the latter two mechanisms to prevent strain from being imposed on the washer strip. The phase is readily adjusted initially by means of the angle bracket 318 (Figs. 2 and 4). As the bracket is shifted to the right or left it moves the worm 314. The axial movement of the worm 314 causes the worm wheel 340 and gearing interconnecting it with the drive disc 48, and consequently the 10 drive disc 48 to rotate slightly relative to the remainder of the gearing and the retainer forming mechanism 56 and drive wheel 166.

A slight alteration of phase between the drum 42 and drive disc 48 is necessary during assembly due to the fact that when the washer strip 46 extends over a progressively increasing axial distance along the drum as the strip is fed from the stack. Due to the frictional fit of the drum on its drive shaft, the shaft only tends to drive the drum and prevents the drum from exerting a drag on the strip. The washer strip 46 thus readily advances the drum slightly relative to the shaft to alter the phase between the drive disc and the drum.

Although a particular form of my invention has been shown and described, it is to be understood that this is for illustrative purposes only and my invention is to be limited only by the following claims.

I claim:

1. In appartus for producing unit assemblies of washers and rotary fasteners, the combination comprising means for continuously feeding washers adjoined to one another in the form of a longitudinal strip at a uniform constant rate, means for relatively twisting the washers of an adjacent pair from the plane of said strip while said strip is advanced at said uniform constant rate to fracture the interconnection and sever the washers from said strip, and means for operating said feeding means and said twisting means in proper timed relation.

2. In apparatus for producing unit assemblies of washers and rotary fasteners, the combination comprising means for continuously feeding a strip of adjoined washers at a uniform constant rate, means for twisting the washers symmetrically substantially about the central longitudinal axis of said strip to sever the washers from said strip, and means for operating said feeding means and said twisting means in proper timed relation.

3. In apparatus for producing unit assemblies of washer elements and rotary fastener elements telescoped therewith, the combination comprising means for feeding a strip of adjoined washer elements and rotary fastener elements telescoped therewith, and mechanism intersecting the path of said strip and constantly rotating about an axis substantially parallel to said strip for engaging one of the elements of each assembly to twist the assemblies to sever the washer elements from said strip.

4. In apparatus for producing unit assemblies of washer elements and rotary fastener elements telescoped therewith, the combination comprising means for continuously feeding a strip of adjoined washer elements and rotary fastener elements telescoped therewith at a uniform constant rate, and mechanism intersecting the path of said strip and constantly rotating about the longitudinal axis of said strip for engaging one of the elements of each assembly to twist each washer relative to the next succeeding washer while said strip is advanced at said uniform constant rate to sever each washer from the remainder of said strip.

5. In apparatus for producing unit assemblies of washer elements and rotary fastener elements, the combination comprising means for continuously feeding a strip of adjoined washer elements and rotary fastener elements telescoped therewith at a uniform constant rate, a rotatable member in the path of said strip having a plurality of arcuately spaced means for receiving and engaging one element of each assembly, and means for rotating said rotatable member about an axis substantially parallel to said strip and in timed relation to said feeding means to twist the washer elements relative to the strip and thereby sever the assemblies from said strip.

6. In apparatus for producing unit assemblies of washer elements and rotary fastener elements, the combination comprising means for continuously feeding a strip of adjoined washer elements and rotary fastener elements telescoped therewith at a uniform constant rate, a rotatable member in the path of said strip having a plurality of arcuately spaced means for receiving and engaging one element of each assembly, and means for continuously rotating said rotatable member at a constant rate in timed relation to said feeding means and about an axis substantially parallel to said strip to twist the washer elements relative to the strip and thereby sever each assembly from said strip.

7. In apparatus for severing washers and headed screw blanks assembled therewith from a strip of adjoined washers, the combination comprising rotatable mechanism having a plurality of arcuately spaced slots for receiving the shanks of said screw blanks and a central bore for receiving the heads of said screw blanks and the washers underlying said heads, and means for rotating said rotatable mechanism about said central bore to twist the washers and screw blanks assembled therewith relative to said strip and thereby to sever each assembly from said strip.

8. In apparatus for severing washers and headed screw blanks assembled therewith from a strip of adjoined washers, the combination comprising a rotatable member having a plurality of arcuately spaced slots adapted to receive the shanks of said screw blanks and a central bore adapted to receive the heads of said screw blanks and the washers underlying said heads, means for feeding said washers and screw blanks through said rotatable member at a continuous uniform rate, and means for rotating said member about said central bore at a continuous uniform rate in timed relation to said washer and screw blank feeding means to twist the washers and screw blanks assembled therewith from said strip.

9. In apparatus for severing washers and headed screw blanks assembled therewith from a continuous strip of adjoined washers, the combination comprising a rotatable member having a central bore adapted to receive the heads of screw blanks and washers assembled therewith and a plurality of recessed portions leading into radial slots through said member and opening into said central bore and adapted to receive the shanks of said screw blanks, means for continuously feeding said assembled washers and screw blanks at a uniform constant rate through said member, and means for continuously rotating said rotatable member about said central bore in the direction of said recessed portions from said slots at a uniform constant rate in timed relation to said washer and screw blank feeding means to twist washers and screw blanks assembled therewith and thereby sever the washers from said strip.

In apparatus for producing unit assemblies of washers and headed screw blanks, the combination comprising a rotatable feeding wheel having peripheral structure for engaging the washers of a strip of adjoined washers and a peripheral slot extending inwardly toward the axis of said wheel to accommodate the shanks of screws telescoped with said washers, means for rotating said feeding wheel, a rotatable member intersecting the path of said strip and having a central bore adapted to receive the heads of said screws and the washers assembled therewith and a plurality of recessed portions each leading into a radial slot through said member and opening into said central bore and adapted to receive the shanks of said screw blanks, and means for rotating said rotatable member about said central bore in the direction of said recessed portions from said slots in timed relation to said feeding means to receive the washer and screw blanks in said central bore and in said recesses and slots to twist each assembly relative to said strip and thereby sever each assembly from said strip.

11. A method of producing unit assemblies of rotary fasteners and washers which comprises feeding a strip of adjoined washers and rotary fasteners telescoped therewith at a continuous uniform rate and twisting the washers symmetrically about the central longitudinal axis of said strip in timed relation to the feeding of said strip while continuing to feed said strip at said continuous uniform rate to sever each washer from said strip.

12. A method of producing discrete unit assemblies of rotary fasteners and washers which comprises telescoping a strip of adjoined washers and a succession of rotary fasteners while moving them at a continuous uniform rate, and therafter twisting the washers about the axis of said strip in timed relation to the feeding of said strip while continuing to feed said strip at said continuous uniform rate to sever the washers from said strip.

13. Apparatus for producing unit assemblies of rotary fasteners and washers which comprises means for continuously feeding a strip of adjoined washers and a succession of rotary fasteners telescoped therewith along a predetermined path at a uniform constant rate, means for directing said strip and the fasteners assembled therewith into engagement with a member constantly rotating about an axis at an angle other than a right angle to said predetermined path while continuing to feed said strip at said uniform constant rate to deflect the washers from the plane of the strip to sever the washers from said strip, and means for rotating said member in timed relation to the movement of said strip.

14. Apparatus for producing unit assemblies of rotary fasteners and washers which comprises means for feeding a strip of adjoined washers and rotary fasteners telescoped therewith along a predetermined path at a uniform constant rate, means for directing said strip and assembled fasteners into engagement with a constantly rotating member along the rotational axis thereof while feeding said strip at said uniform constant rate to twist each washer relative to the next succeeding washer about the axis of said strip to sever each washer from said strip, and means for rotating said member in timed relation to the movement of said strip.

15. In apparatus for producing unit assemblies of washers and rotary fasteners, the combination comprising means for directing a strip of contacting, interconnected washers over a predetermined path, means for feeding a succession of rotary fasteners over a path relatively converging with the path of said strip to bring said fasteners and the washers of said strip into telescoping relation, and continuously operating means engaging opposite peripheral edges of the washers of said strip for feeding said strip after assembly with said fasteners at a continuous uniform predetermined rate.

16. In apparatus for feeding a strip of adjoined washers and screw elements assembled therewith, a washer strip feed wheel having a circular outer periphery with a slot extending inwardly therefrom to accommodate screw element shanks, the slot being of much greater extent radially of the wheel than axially, and a plurality of substantially semicircular recesses spaced along said slot and adapted to engage successive washers of a strip of adjoined washers, and means for driving said wheel to feed said strip.

17. In apparatus for feeding a curved strip of adjoined washers and screw elements assembled therewith, a washer strip feed wheel having a substantially frusto-conical periphery with a substantially conical slot extending inwardly therefrom to accommodate screw element shanks and a plurality of substantially semicircular recesses spaced along said slot and adapted to engage successive washers of a curved strip of adjoined washers, and means for driving said wheel to feed said strip along Y a curved path.

fasteners telescoped therewith at a uniform constant rate, means for twisting each washer relative to the next succeeding washer from the plane of 'said strip while said strip is advanced at said uniform constant rate to sever each washer from said strip, and means for operating said twisting means in timed relation to said telescoped strip and fastener feeding means.

19. Apparatus for assembling rotary fasteners and washers comprising means for receiving a coiled strip of adjoined washers, means for feeding said strip over a spiral path from the coil, means for feeding a succession of rotary fasteners synchronously with the movement of said strip of washers over a curved path relatively converging with said spiral path to bring said fasteners and the Washers of said strip into telescoping relation, and means operable in timed relation with the movement of said strip for twisting each washer relative to the next succeeding washer about the axis of said strip to sever each washer from said strip.

20. Apparatus for assembling fastening elements and washer elements comprising means for feeding a strip of adjoined washer elements over a predetermined path, means for feeding a succession of fastening elements synchronously with said strip of washer elements over a path relatively converging with the path of said strip to bring said fastening elements and said washer elements into telescoped relation, means for displacing a section of metal from one of each pair of telescoped elements to retain the other element of each pair in telescoped relation therewith, and means rotating in timed relation to the movement of said strip about an axis at an angle other than a right angle to the longitudinal axis of said strip for deflecting each washer element relative to the next succeeding washer element from the plane of said strip to sever each washer element from said strip.

21. Apparatus for assembling fastening elements and washer elements comprising means for feeding a strip of adjoined washer elements over a predetermined path, means for feeding a succession of fastening elements synchronously with said strip of washer elements over a path relatively converging with the path of said strip to bring said fastening elements and said washer elements into telescoped relation, means for displacing a section of one of each pair of assembled elements to retain the other element of each pair in telescoped relation thercwith, and means for twisting each washer element relative to the next succeeding washer element about the axis of said strip in timed relation to the movement of said strip to sever each washer from said strip.

22. Apparatus for assembling fastening elements and washer elements comprising means for feeding a strip of adjoined washer elements over a predetermined path, means for feeding a succession of fastening elements synchronously with said strip of washer elements over a path relatively converging with the path of said strip to bring said fastening elements and said washer elements into telescoped relation, means for deflecting a section of one of each pair of telescoped elements to retain the other element of such pair in telescoped relation therewith, a rotatable member having an axial bore and arcuately spaced radial slots extending therefrom for receiving successive assembled fastening elements and washer elements, means for feeding said strip of washer elements and the fastening elements assembled therewith at a uniform constant rate into said axial bore and some of said slots, and means for constantly rotating said rotatable member in timed relation with said last named feeding means.

23. In apparatus for producing unit assemblies of washer elements and fastener elements telescoped therewith, the combination comprising means for feeding a strip of adjoined washer elements and fastener elements telescoped therewith, means intersecting the path of said strip and rotatable about an axis substantially parallel to said strip for engaging one of the elements of each assembly to twist the assemblies to sever the Washer elements from said strip, and means for rotating said rotatable means in timed relation to the strip feeding means.

24. The combination as set forth in claim 23 wherein the rotatable means is rotatable substantially about the longitudinal axis of the strip.

25. In apparatus for severing washer elements and fastener elements assembled therewith from a strip of adjoined washer elements, the combination comprising rotatable mechanism having a central opening for passing the assembled elements and having means for engaging one of each assembled pair of elements, and means for rotating said rotatable mechanism about said central opening to twist the washer elements and fastener elements assembled therewith relative to said strip and thereby to sever each assembly from said strip.

26. In apparatus for producing unit assemblies of washer elements and fastener elements telescoped therewith, the combination comprising means for feeding a strip of adjoined washer elements and fastener elements telescoped therewith, means intersecting the path of said strip and rotatable about an axis angularly arranged relative to said path at an angle other than a right angle for engaging one of the elements of each assembly to twist the assemblies to sever the washer element from said strip, and means for rotating said rotatable means in timed relation to the strip feeding means.

27. In apparatus for producing unit assemblies of washer elements and fastener elements telescoped therewith, the combination comprising means for feeding a strip of adjoined washer elements and fastener elements telescoped therewith, means intersecting the path of said strip and movable substantially transversely of said path at a point spaced from the center line of said strip for engaging one of the elements of each assembly to twist the assemblies from the plane of the strip to sever the washer elements from said strip, and means for moving said intersecting means in timed relation to the strip forwarding means.

References Cited in the file of this patent UNITED STATES PATENTS 744,244 Semrner Nov. 17, 1903 1,876,174 Stoler Sept. 6, 1932 2,201,058 Staubli May 14, 1940 2,271,154 Niskanen Jan. 27, 1942 2,284,676 Nielson June 2, 1942 2,284,698 Trotter June 2, 1942 2,352,118 Poupitch June 20, 1944 2,390,121 Poupitch Dec. 4, 1945 

